Earth drill



June 27,1944.

C. W. KANDLE EARTH DRILL- Filed Oct. 29, 1942 Charles WKandle I NVENTOR.

AT TOENES.

Patented June 27, 1944 UNITED STATES PATENT OFFICE,

2,352,326 f Y f EARTH DRILL Charles W. Kandle, Chicago, 111.

Application October 29, 1942, Serial No. 463,776

3- Claims.

This invention relates to improvements in earth drills of the kind employed with portable power drilling units adapted to dig post holes and the like in various types of soil.

The invention has been employed in the drilling of relatively large diameter holes, usually considerably in excess of ten inches in diameter, where the spiral lift construction for removing spoil from the hole is impractical and too heavy and expensive. It utilizes the principle of a lifting bucket for receiving the spoil from the cutter blade.

The principal object of the invention is to provide a combination drill and bucket that is more eificient in use.

Another object is to provide a bucket with the cutting blade in a substantially closed flat bottom to obtain a cleaner hole.

A more specific object is to provide a partition in the bucket located to prevent dirt in the bucket from interfering with the incoming spoil.

Another specific object is to prevent the escape of dirt from the bucket during lifting.

Another object is to provide for more ready lifting and lowering of the bucket and drill without interference from the side wall of the hole being drilled.

The invention is illustrated in the accompanying drawing in which:

Figure 1 is a side elevation of the drill;

Fig. 2 is a perspective view thereof with parts broken away and sectioned to show the cutter blade and baflle;

Fig. 3 is a top plan view of the drill with the drive shaft sectioned on line 3-3 of Fig. 1; and

Fig. 4 is a transverse horizontal section of the bucket taken on line 4-4 of Fig. 1.

Reference is made to applicants copending application, Serial No. 362,020, filed October 21,

1940, for Drill bit, which discloses a drill bit comprising a horizontal circular plate with a radial cutting blade therein and having a central upright shank and downwardly extending blunt lead screw.

The present invention employs a similar circular plate I as the bottom of a cylindrical bucket 2. The plate I may be relatively thinner than that set forth in the application referred to since the side walls of the bucket have sufficient vertical extent to keep the drill properly centered in the hole. The bucket 2 is open at the top.

The cutter blade 3 is disposed at the rear edge of a radially extending slot in plate I and is adjustably set at an angle with its lower cutting edge below the bottom of plate I to cut andlift" the spoil into the bucket as the latter rotates. The blade 3 extends at a slight angle to the radius with the outer end advanced relative to the inner end to effect inward movement of the spoil away from the outer wall of the hole.

The central upright shank 4 is secured to the plate I at its center and extends upwardly as the drive shaft for the drill. The central lead screw 5 has its upper end extending through plate I and secured in the lower end of shank 4. The lead screw extends downwardly to pull the drill downwardly and assist in preventing the blade 3 from riding above the surface and failing to cut, particularly in hard ground.

The bucket has an upright partition or baflle 6 which is secured to the central shank 4 and to the cylindrical side wall of the bucket 2 and extends from the bottom I to the open top of the bucket. The baille 6 either rests upon or is secured to the plate I adjacent the forward edge of the slot in the plate and extends vertically upward to prevent spoil which is pushed around the bucket from interfering with the entrance of additional spoil through the slot. If desired, the upper portion of the baffle 6 can be offset rearwardly to provide additional storage capacity for dirt in the bucket. In such case the offset 1 is preferably horizontal and disposed a substantial distance above the slot in plate I.

While the bailie 6 might be made slanting at an angle in some cases, it has been found best to employ a vertical baflle and to provide a substantially horizontal offset at a suflicient distance above the slot to prevent interference with spoil rising over the blade 3.

Additional radial braces 8 are provided at the top of the bucket between shaft 4 and the wall of the bucket 2 to hold the latter concentric with the shaft.

For the purpose of providing a clean side wall for the hole and of facilitating removal of the bucket, a spiral rib 9 is disposed around the cylindrical wall of the bucket 2 and spot-welded thereto. The convolutions of the rib 9 are in a direction to effect the raising of spoil along the outside of the bucket as the latter rotates. The spoil raised in this manner reaches the top of the bucket and falls into the bucket. The rib 9 also serves to cut the hole a little larger than the bucket and thereby prevent sticking of the bucket in the hole.

The drill is rotated by tubular shaft 4 which extends upwardly for a suitable unitary distance, such as four feet, and is pinned to a coupling member ID. The member ID is in turn pinned to an adapter chuck I I or to a shaft extension. The chuck II is secured to a rotary head of an air mo tor I2 or other suitable portable driving unit.

The drill is suitable for drilling almost any kind or type of soil. When large rocks are encountered, they must either be removed or broken into pieces before continuing the drilling operations.

Where sand and light soil is encountered, a hinged trap door I3 is provided over the slot in plate I to prevent back seepage and loss of spoil in the bucket when the latter is being lifted out of the hole. The door I3 is hinged at the forward edge of the slot in plate I and is disposed to lie across the slot by its own weight to close the bottom of the bucket, while allowing spoil to push it upwardly and to enter the bucket through the slot during drilling operations.

The drill has been employed in drilling holes as large as two and three feet in diameter and can be used in cleaning out manholes and the like and in drilling various holes of large size for military, mining and other purposes. It is also adaptable for drilling small diameter holes as in the sampling of soil in prospecting, and the like.

The invention may have various embodiments within the scope of the accompanying claims.

I claim:

1. In combination for drilling earth, a cylindrical bucket with a substantially flat bottom, a cutting blade disposed in a radial slot in the bottom, and a stationary shield in said bucket disposed ahead of said slot to prevent interference with incoming spoil by the spoil previously deposited in said bucket, said shield extending upwardly from the bottom of said bucket and rearwardly over said blade at a substantial height above the same.

2. In combination for drilling earth, a cylindrical bucket with a substantially closed bottom, a cutting blade disposed in a radial slot in the bottom, a drill shaft secured to said bottom and extending upwardly centrally of the bucket for rotating the same, and a fixed baflle plate extending between said shaft and the wall of the bucket ahead of said slot to prevent clogging of spoil in said slot, said baflie plate extending upwardly from the bottom of the bucket and rearwardly over the blade with sufiicient clearanc above the blade to prevent clogging of spoil as the latter passes over the blade.

3. In combination for drilling earth, a cylindrical bucket with a substantially closed bottom, a cutting blade disposed in a radial slot in the bottom, a drill shaft secured to said bottom and extending upwardly centrally of the bucket for rotating the same, and a substantially vertical plate extending between said shaft and the side wall of said bucket, said plate engaging the bottom of the bucket adjacent the forward side of said slot and having a rearwardly extending ledge overhanging said slot to add to the storage capacity of the bucket.

CHARLES W. KANDLE. 

